Skip to main content
Accessibility Resource Center Skip to main content
Have a phone you love? Get up to $500 when you bring your phone. OR get iPhone 13, on us for a limited time. With Select 5G Unlimited plans. Buy now
end of navigation menu
No dial tone at both jacks

Here's the details of what I am encountering with my landline phones.  (Copper wires).  I have an AT&T 2.4 GHz cordless telephone/answering system, E2725, which has an extension phone.  They are not new.  I've been at my present location for eight years and have had no problems with my service before.

A couple weeks ago both phones stopped working simultaneously after it rang once.  The ring was not as loud as normal.  I thought the caller hung up.  No dial tone.  Some static.  "In use" light blinking.  Phones say "Ext. In Use," even though I never answered the phone or removed a receiver from the base.

A little later that same day it went back to normal.  I made some phone calls.  Then the same thing happened and no more dial tone.

The next day I tried a corded phone at both jacks and had the same problem, no dial tone and static.  I went out to the NID box and plugged the corded phone in and got a dial tone.

Things remained that way for about a week.  Then I noticed the "in use" light had stopped blinking.  Monday I was able to send a fax and make a call.  Wednesday the phone rang softly again.  I never had a chance to lift a receiver off the base. The next time I looked at the base, the "in use" light was blinking again, no dial tone and some static.  This morning the "in use" light had stopped blinking again.  This afternoon it's blinking once more.  This time no call came in.

This is what I found at AT&T's website:



Display shows "Extension In Use".


Please review the below solution(s) to assist with the problem(s) you may be encountering.

   1. Line voltage is incorrect. Shows "Extension in Use".

      The line voltage on the customer's line is too low. "Extension in Use" will appear on the screen when the line voltage drops below 21 volts. Normally, this would only happen when another phone on the line was off hook. Contact your local telephone company for assistance; additional charges to be incurred by customer may apply.

   2. Normal Operation. Display shows "Extension in Use".

      Normal Operation. The unit will show "Extension In Use" when another set on the line is in use. It shows this because the unit has sensed a change in line voltage. If there is not another phone off hook when it shows this message, that is due to a temporary fluctuation in the line voltage. There is nothing malfunctioning with the unit.

What does one need to do when the voltage isn't correct?  The only thing I noticed at the NID box was that there was some corrosion and oxidation of a few wires and terminals.  I checked for crossed or touching wires, but saw none.  I checked for damage to the lines coming into our home, but I found no damage.  Any help would be appreciated.



Re: No dial tone at both jacks
Enthusiast - Level 3

When we had that problem we found that our older answering machine was the root of the problem.